DRAFT TANZANIA STANDARD  
 
 
TBS/ GTDC4  (6327 ) P3 – Blow Moulded polyolefin  containers — Specification  
(Part 2 : Over 5 l itres up to and including 60 l itres capacity) . 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 1 Scope  
This standard (Part  2) specifies tolerances on dimensions, performance requirements and methods of 
sampling and tests for free standing blow moulded containers, made from polyolefin, with capacities 
over 5 litres up to and including 60 litres and having an internal neck diamete r not exceeding 75 mm.  
This standard does not cover containers specifically intended for products classified as dangerous 
goods.  
2 Normative references  
The following referenced documents are indispensable for the application of this document. For dated 
references, only the edition cited applies. For undated references, the latest edition of the referenced 
document (including any amendments) applies . 
       IS 2798 : 1998  Methods of test for plastic containers ( first revision )  
       IS 7408:2000  Blow Mou lded polyolefin  containers — Specification . 
  
  IS 8747: 1977  Method of test for environmental stress crack resistan ce of blow moulded 
polyethylene containers . 
 
      IS 7028 -1 Performance Tests for Complete, Filled Transport Packages, Part 1: Stacking Tests 
using Static Load  
 
3.Terms and definitions  
For the purpose of this document, the following terms and definitions shall apply ; 
 
3.1 Blow Moulded Container  
container formed fr om a parison of heat softened thermoplastics material by the application of 
pressure which forces it against the inside walls of a blow mould   
3.2 Brimful Capacity  
volume of liquid held by the container when filled to the point of overflowing while st anding on a level 
with al l closures removed  (see Fig.1)  
 
3.3 Container Height to Neck Face  
height of the highest point of the neck face of the finished empty container  (see Fig.1)  
 
3.4  Container  Overall  Height  
height of finished empty container at its highest point excluding the closure  (see Fig.1)  
 
3.5 Container Overall Plan Dimensions  
principal plan dimensions of the container, for example, the external diameter of  a cylindrical 
container  
 
 3.6 External Neck Diameter  
external diameter of the neck, excluding thread and  / or prominences, measured as the mean of two 
perpendicular diameters avoiding the pan line  
 
 
 
 
 3.7 Internal Neck Diameter  
minimum internal  diameter of the neck whether it be parallel,  tapered or internally threaded  
3.8 Gross Capacity  
total enclosed volume of the container including any space which may not be capable of being filled  
 
3.9 Nominal capacity  
 volume of liquid the container is intended to hold at 27±20C 
3.10 Neck Face  
 upper most surface of the container neck  (see Fig.1)  
3.11 Neck Height  
The perpendicular distance from the highest point of the plane including the neck face to the nearest 
point of the finished container shoulder along a line passing through  
a) in the case of screw threaded necks, the outermost edge of the thr ead; a feature 
below the thread of greater diameter than the thread is considered as  a part of the 
container's shou lder; 
b) in the case of plain cylindrical and internally threaded necks, the outermost diameter 
point excluding flash; and  
c) in the case of neck h aving a bead and thread, or bead only. the outermost point of the 
bead  
NOTE -A bead is separated from the conta iner by a region of diameter smaller  than that of th e 
bead.  
3.12 Thread Diameter  
external diameter of the neck thread measured as the mean of two perpendicular diameter avoiding 
the part line  
 
3.13 Fill point  
vacuum space between nominal capacity and brimful capacity of the container  
 
 
     NECK  
  
   
 
 4 Capacity  
A recommended range of nominal capacities for stock containers for liquid products, together with the 
corresponding minimum brimful capacities, is given in Table 1. When the container is filled to nominal 
capacity, the liquid level shall be below the bottom of the closu re neck, with the container standin g 
level on its base . Capacities shall not be measured within 48 h of production. The water used shall be 
at a temperature of  27 ± 2° C. 
    Table 1 - Recommended Nominal Capacities  / Brimful Capacities for Stock Containers  
 
S/No. Nominal Capacity (litres)  Minimum Brimful Capacity (litres)  
1.  10 10.5 
2.  20 21 
3.  25 26.25  
4.  30 31.5 
5.  50 52.5 
6.  60 63 
 
6 Tolerances a nd dimensions  
 The tolerances a nd dimensions specified refer to finished empty containers. Dimensions of filled 
containers may show differences.  All measuring equipment shall be capable of measuring to an 
accuracy of 10 percent of the agreed tolerance.  
 
6.2 Container height to Neck Face  
The tolerance on container height to neck face shall be  ±1 percent  compared to nominal value . The 
height shall be measured with accordance with method described in Annex A. 
6.3 Container Overall Height  
The tolerance o n container overall shall be ± 1 percent , whichever  is greater. The height shall be 
measured in accordance with the method described in Annex B .1. 
 
6.4 Neck Height  
The tolerance on neck height shall be ± 2.0 percent . The neck height shall be measured in 
accordance wi th the method described in Annex  B.3. 
 
6.5 Neck and Thread Diameters  
The tolerance on neck and thread diameters shall be ±1.25 percent compared to declared nominal 
value . These diameters shall be measured in accordance with the method described in Annex  B.4 
 
6.6 Thread Diameters  
The length of thread in contact between cap and neck shall be  a minimum of 1 1/2 turns. The major 
and minor thread diameters shall each be measured in accordance with the method described in 
Annex B.4 . The tolerance on thread diameters shall be as agreed to between the purchaser and the 
supplier.  
 
 6.7 Fill point  
The fill point level shall be agreed upon between purchaser and supplier depending on the indented 
use of the container  
 
 
 7 Performance requirements  
7.1 Drop Impact Strength  
The container when subjected to the drop test by the method described in Annex C  shall show no sign 
of ruptur e or leakage from the walls of t he container Slight deshaping of the body shall not render the 
container unacceptable in the test.  
7.3 Stack Load Test  
The containers shall not show any cracks or permanent bul ging likely to reduce their strength, cause 
leakage or reduction in effectiveness of the closure or cause instability in stacks when tested in 
accordance with the method described Annex D  
7.4 Environmental Stress -Crack Resistance  
The containers when tested in accordance with Method I of IS 8747  shall show no evidence of stress  
cracking or leakage after being kept in the oven for 48 h.  
 
7.7 Ink Adhesion of Printed Containers  
The printed matter on the containers when tested in accordance with the method described Annex E  
shall be still legible.  
7.8 Product Resistance of Printed Containers  
The printed matter on the containers when tested in accordance with the method described i n Annex 
F shall be still legible  
7.9 Test for Compatibility  
The containers shall be tested for determination of compatibility for an intended purpose as per the 
method described in Annex  G. 
 
8 Handle Strength  
The handles and the containers shall remain intact and undamaged when tested in accordance  with 
the method described in Annex H . 
 
9 Closures  
The closure shall be of a material as resistant to the product as is the container itself and shall 
correspond to the type and form of the container so as to ensure a good and leak proof fit when 
tested in accordance with the method described in  Annex I . Thread closures shall be tightened to a 
torque as agreed to between the purchaser and the supplier . 
 
10 Marking  
 The containers shall be legibly and indelibly marked with the following information  
 
a) Manufacturer's name, initials or trade -mark.  
b) Nominal capac ity of the container in ml or litres . 
c) Batch No. and year of manufacture . 
d) Recyclable/non -recyclable symbol.  
e) Plastic identification code . 
 
 
 
 
 
 
 11 Sampling  
11.1 Samples  of the  container shall be drawn and conformity of the lot this  specification as prescribed 
in clause 10. 2. The  container shall be type tested for the requirements given in clause 7.2 and 7.3. 
Any change in design, material or capacity makes it necessary for the new containers to be tested in 
accordance with all the tests s pecified. The tests given in clause 7.7 and 7.8  are applicable only to 
printed containers.  
 
11.2 Scale of sampling  
11.2.1  Lot 
In consignment, all the containers of the same material drawn from a single batch of manufacture 
shall be grouped together to constitute a lot.  
11.2.2  For ascertaining the conformity of the containers to the requirements of this standard, test 
shall be carried out separately for each lot. The number of containers  to be sampled from a lot 
shall be in accordance with Table 2 .  
11.2.3  The containers shall be selected at random from the lot.  
11.3 Number of tests and criteria for conformity  
11.3.1  The number  of tests and criteria for conformity shall be determined according to Table 3 . 
11.3.2  Drop Impact Strength and Stack Load Test  
One set of sample containers as given in the test methods ( 7.2 and 7.3)  shall be drawn from the lot 
and these shall be subjected to the respective tests. The sample shall pass the tests for acceptance 
of the  lot in respect of drop impact and stacking requirements . 
 
Table 2  -Scale of Sampling and Permissible Number of Defectives  
(Clause s 11.2.2 and 11.3 ) 
 
S/No.  
 
 
 
 
(1) Lot size  
 
 
 
 
(2) For Non -Destructive Tests  For wall Thickness 
Measurement, Sub -
Sample size (Number of 
Containers to be Selected)  
(5) Sample size ( Number of 
Containers to be Selected)  
 
 
(3) Permissible Number 
of Defective  
 
 
(4) 
1.  Up to 100 5 0 2 
2.  101 to 300  13 1 2 
3.  301 to 500  32 3 2 
4.  501 to 1000  50 5 3 
5.  Over 1000  80 7 5 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 Table 3 - Number of tests and Criteria for Conformity  
(Clause  11.3.1 ) 
 
S/No.  
(1) Characteristics  
(2) Clause Ref.  
(3) Number of Tests  
(4) Criteria for 
Conformity  
(5) 
1.  Brimful capacity  4 According to column 3 of 
table 4   The number of 
defective containers 
for one or more 
characteristics does 
not exceed the 
corresponding number 
given in column 3 of 
table 4  2.  Container mass  5 
3.  Dimensions  6.2,6.3,6.4,6.5,6.6,6. 8, 
and 6.9 
4.  Closure leakage  7.1 
5.  Hydrostatic pressure  7.4 
6.  Wall thickness  6.7 According to column 5 of 
table 4  All the containers 
satisfy the relevant 
requirements  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 ANNEX A  
(Clause 6.2)  
MEASUREMENT OF CONTAINER HEIGHT TO NECK FACE  
A1. Ascertain  the container height to neck face by placing the empty container on a flat surface and 
measuring to the highest point on the neck face using a micrometer height gauge.  The measurement 
shall be to an accuracy of 0.05 mm . 
 
ANNEX B  
(Clause 6.3,6.4,6.5 ,6.6) 
MEASUREMENT OF DIMENSIONS  
B.1 Overall Height  
B..1.1 Apparatus  
B..1.1.1 Micrometre height gauge  
B..1.2 Procedure  
Place the container on  a surface plate and measure to the highest point on t he container using a 
micrometre height gauge at two positions as follows:  
a) Close to but avoiding the part line; and  
b) At 90’ t o the position specified at (a).  
B..1.3 Calculation  
The height is recorded as the mean of the two readings. The accuracy or measurement shall be 0.1 
mm. 
B..2 Diameter  
B..2.1 Apparatus  
B..2.1.1 Vernier micrometer or circumference gauge  
B.2.2 Procedure  
The container diameter shall be ascertained by either of the micrometer or circumference gauge 
method.  
B..2.2.1 Micrometer method  
By using a Vernier or mic rometer, measure the diameter of the con tainer at a specified height as 
follows:  
a) Close to but avoiding the part line; and  
b) At 90’ to the position specified at (a).  
The accuracy of m easurement shall be 0.1 mm. The diameter is recorded as the mean of th e two 
diameters at right angles.  
B..2.2.2 Circumference gauge method  
By using a circumference gauge, measure the circumference at a specified height.   
Record the diameter as the circumference multiplied by 0.318.  
 
 
           NOTE - The circumference gauge normally gives the mean  diameter directly . 
B.3 Measurement of Neck Height  
B..3.1 Apparatus  
B..3.1.1 Micrometer depth gauge  
B..3.2 Procedure  
Place the anvil of the depth gauge on the neck face, and move the instrument laterally until the 
spindle touches the outermost neck feature. See that the tip of  the spindle is allowed to touch the 
container shoulder and read the scale.  
B.3.3 Calculation  
Record the neck height as the mean of the two readings taken at right angles at  the neck face . 
B.4 Measurement of Neck and Thread Diameters  
B.4.1 Apparatus  
B.4.1.1 Micrometer  or Vernier, giving an accuracy of measurement of 0.02 mm.  
B.4.2 Procedure  
B..4.2.1 Measure the neck with a vernier or micrometer as  follows:  
a) Close to but avoiding the part line; and  
b) At 90° to the position specified at (a).  
B..4.3 Calculation  
The diameter is recorded as the mean of the two diameters at right angles . 
 
B.5 Measurement of Wall Thickness  
B..5.1 Apparatus  
B..5.1.1 Micrometer/screw gauge, fitted with ball point tips or dial calliper gauge fitted with spherical 
anvils giving an accuracy of measurement of 0.02 mm.  
B..53 Procedure  
The container wall th ickness shall be ascertained by either of the methods indicated below.  
B..5.2.1 Micrometer me thod 
Cut the container horiz ontally into three pieces (top.  Middle and bottom) with a pai r of scissors or 
hacksaw blade. Measure the w all thickness with a micrometer or screw gauge fitted with  ball point tip, 
at four places in each section. Take t he average of four readings and report as wall thickness at top, 
middle and botto m. 
B..5.2.2 Dial calliper gauge method  
Measure the wall thickness with the help of dial calliper  fitted with spherical anvil s, Care shall be taken 
to avoid movement of the con tainer during measurement as this may affect the re ading obtained. The 
measurement shall be to an accura cy of 0.02 mm. Take the mean of three readings at any lo cation 
(top, middle and bottom) as wall thickness.  
 
  
 
  
ANNEX C  
(Clause 7.2 ) 
DROP IMPACT TEST  
C.1 Principle  
 
The drop test is used to measure the ability of the container to withstand rough handling while in a 
packed condition.  
 
C.2 Equipment . 
 
Any suitable equipment may be used provided that it conforms to the following requirements:  
 
a) Permits accurate prepositioning of the container to assure an unobstructed fall from rest and 
impact at the specified places and in the desired direction;  
b) Permits accurate and convenient control of the height of drop; and  
c) Provides a solid surface of c oncrete to absorb all shock without deflection.  
 
C.3 Drop Height  
 
Unless specified otherwise in the container standard, the drop height of the containers up to 5 kg or 5 
litres capacity shall be 1.2 m, for containers of 10 kg or 10 litres capacity 1  m and for containers of 15 
kg or 15 litres capacity it shall be 0.5 m respectively.  
 
C.4 Sample Size  
The sample size shall be six containers, taken at random from a batch, divided into two sets of 3 
each, designated as Set 1 and Set 2.  
 
C.5 Procedure  
 
C.5.1 Fill each containers to its nominal capacity with water at standard conditions as specified in the 
specification of the individual containers (in case, conditions have not been specified, it shall be taken 
as ambient conditions).  
 
C.5.2 Close each container with its usual closure with the inner seal heat sealed to its mouth. Drop 
the containers under free fall condition in Set 1 squarely on their base on to a rigid flat horizontal 
surface of steel or smooth concrete as the dropping  surfac e. 
 
C.5.3 Drop the containers under free fall condition in Set 2  on their side (the body of the container 
being parallel to the impacting ‘floor) onto the dropping surface.  
 
C.5.4 The containers shall not rupture nor shall there be any leakage  from the wal ls of the container. 
Slight deshaping of the body shall not render the containers unacceptable in the test.  
 
NOTE - If the liquid to be packed is of high density, the material itself or a suitable material of 
similar density should b e used instead of water.  
 
C.6 Test at 0°C  
 
C.6.1.This test i s normally carried out only for multi -tip containers  for transport  of hazardous goods  
liable to be sub jected to low temperatures. The container shall be filled  to the nominal capacity with a 
liquid at tes t temperature (for example, for polyethylene containers ,12 percent methylated spirit in 
water or an ethylene glycol/water mixture  is suitable). The filled containers shall  then be chilled to a 
temperature  in the rang e -4 to 0°C and stored  at that range for at least 4 h.  
  
 
 C.6.2 The containers shall be subjected to drop test as per the procedure specifi ed at G .5. 
 
 
ANNEX D  
(Clause 7.3 ) 
STACK LOAD TEST  
 
D.1 Principle  
 
A force is applied  to the top face of the package equivalent in magnitude t o the total weight of 
identical packages stacked on t op to a minimum stack height of 3 m. The duration is 24 h.  
 
D.2 Sample Siz e 
 
Four containers shall be used for each single test.  
 
D.3 Procedure  
 
Fill the containers wi th water at ambient temperature up to nominal capacity a nd close with the usual 
closure to the nominal torque (i f the liquid to be packed is of high density, it shoul d be used as the test 
medium).  
 
Arrange the cont ainers in a block at 2 x 2 on a rigid, level, flat surface. Appl y a top load evenly 
distributed on a flat plate placed  on the unsupported containers.  The total superimposed load along 
with the load of the flat surface for different sixes of containers shall  be as specified in the 
specifications of the individual container.  
 
Examine  the containers  after 24 h of test period. The containers shall not show any cracks or 
permanent  
buckling likely to reduc e their strength, cause leakage or reduction in effectivenes s of the closure or 
cause instability in stacks.  
 
 
ANNEX F  
(Clause 7.7) 
 
 TEST FOR INK ADHESION OF PRINTED CONTAINERS  
 
F.1 Procedure  
 
F.1.1 Apply two strips of 25 mm wide transparent pressure sensitive tape or ce llo tape to the printed 
area of container; one piece d own the length of the container and the other round the circumference.  
 
F.1.2 Press the tape firmly o n to the container and leave it for 15 seconds.  
 
F.1.3 Remove the tape by pulling slowly at about 1 cm/s from one end at about 90 ° to the container 
surface.  
 
F.1.4 There shall be no signif icant removal of the print from the surface of the c ontainer and the print 
shall be legible to the naked eye after the test.  
 
 
  
 
 ANNEX G  
(Clause 7.9) 
 
TEST FOR COMPATIBILITY  
 
G.1 General  
 
This method is for de termination of compatibility of plastics container s for an intended purpose . For 
specific application  for packaging of food, pharmaceuticals and dr inking water, further reference may 
be made to Standards  on Specific Products . 
 
G.2 Principle  
 
Piece  of plastics mater ial with which the container is made are treated at a n elevated temperature 
with the liquid which the containe r is intended to transport. Any changes in organoleptic 
characteristics, weight, dour or flavour, size, shape an d colour that occur in the test specimens are 
noted. For dry produ cts, the tests may be carried out only on  the containers filled with the product as 
in I.4.2. 
 
G.3 Test Specimens  
 
G.3.1 Material  
 
Three test pieces of a pproximately 15 cm  x 15 cm size shall be cut from any co nvenient part of the 
container.  Each test piece shall be cleaned, wiped and dried. It shall be measured for  length, width 
and thickness to the nearest 0.05 mm and weighed to the nearest milligram.  
 
 
G.3.2 Container  
 
Six samples of specific  container intended for packing of particular product sha ll be tested in 
accordance with the test procedure given at I.4.2 
 
G.4 Procedure  
 
G.4.1 Testing of Material  
 
The liquid ,which is intended to be tilled in the container shall be introduced into a glass vessel and  
test piece s completely immersed, avoiding unnecessary contact wit h the other pieces or the walls of 
the glass vessel . Where the density of plastics material is less than that of the liq uid, small weights,  
inert to the liquid, may be used to prevent the test pieces f rom either floatin g or curling. The test shall 
be carried out continuousl y over 28 days at a temperature of 50 f 2°C. The liqu id and the test pieces 
shall be thoroughly agitated every 24 h.  
 
After the required te st period has elapsed, the test pieces shall  be removed from the liquid, suitably  
cleaned, drie d, weighed and measured as in I .3.1. 
 
G.4.2 Testing of Container  
 
In order  to assess the compatibility of the container, the container shall be filled with the product to 
nominal capacity, sealed an d capped in the manner intended and kept at a temperature of 50 f PC for 
a period of 28 days. At the end of t his period the containers shall be examined for the following:  
 
a) Visible cracks, if any;  
b) Change in colour;  
c) Change in weight; and  
d) Change in shape.   
 
  
G.5 Test Result and Interpretation  
 
G.5.1 Any change in weight, dimensions or alterations in other c haracteristics (such as colour.  
Blooming, etc.) or any other deteriorati on in quality of the product shall be used by manufacturer and  
purchaser in reaching a greement as to the stability of the plastics material for its intended purpose.  
 
G.5.2 Further Testing  
 
Where, in the opinion of  either the manufacturer or the purchaser, it is conside red that further 
information on compatibility is required (for example at low temperature) further testing may be carried 
out on a sample container filled with liquid to be transported. Precise requ irements shall be 
determined by agreement betw een the manufacturer and the purchaser.  
 
I.5.3 The actual stora ge test shall be carried out at the room temperature f or one -third of the 
anticipated shelf life period for the products that are not stable at the suggested temperature of 
50±2°C. 
 
 
ANNEX H 
 
(Clause 8)  
 
HANDLE PULL TEST  
 
H.1 General  
Two methods are prescribed, namely Method A and Method B.  
 
H.2 Sample Size  
 
Three containers shall be used for each single test.  
 
H.3 Method A  
 
H.3.1 Apparatus  
A suitable device to hold the container firmly in inverted position near the shoulder.  
 
H.3.2 Procedure  
 
Fill the container to the nominal capacity with water and close in the norm al manner. Fix the container 
in inverted position and at tach weight equal to double the nominal capacity o f the container through a 
hook.  Keep for 24 h an d examine for any damage to the handle or the hinges.  
 
H.4 Method B 
 
H.4.1 Proc edure  
 
Fill one of conta iners with water to its nominal capacity and secu re the closure. Attach a rope to the 
balance point of the handle of the container leaving 300 mm slack.  Allow the cont ainer to fall freely for 
30 cm. Subject the container to two further drops.  There shall be no damage to the handle or the 
hinges.  
 
 
 
 
 
 
 
 
  
 
 ANNEX I  
(Clause 7.1 ) 
CLOSURE LEAKAGE  
I.1 Procedure  
I.1.1 Fill the container up to nominal capacity with coloured  water or the m aterial to be packed at 
ambient temperature, and close t ight with the closure. Keep the container in an invert ed position on a 
white blotting paper without any e xternal support for at least 30 minutes. The cont ainer shall be 
examined for any leakage which wo uld be evident from any visible stains on the blotting paper.  
 
The method helps to determine the ability of a closure  (on a container) to prevent leakage due to the  
transportational vibration.  
 
I.2 Vibration Table  
 
I.2.1 The vibration table, o f sufficient size, rigidity and mass -carrying capacity, supported on a 
mechanism  
that shall maintai n the surface horizontal during vibration. The difference in surface level between the  
table extremities shall not exceed 10 mm.  
 
The table may be equipped with:  
 
a) low fences to restrict sideways and endways  movement during testing;  
b) high fences or other means of maintaining a  superimposed load in position on the test 
container  
            during testing; and  
c) means to simulate the method of restraining the  container during transit  
 
In addition, the appara tus shall meet the requirements and tolerance given in I.2.2. 
 
I.2.2 Procedure  
 
I.2.2.1  Fill the container to its nominal capacity with the  product or coloured water and close it with the 
usual  closure in the manner in which it is intended to be used.  
 
I.2.2.2 Place the test container in the predetermined attitude  on the vibration table ( see I.2 ), with the 
centre of its  lowest face or its centre of gravity as near as  practicabl e within 10 mm of the centre of 
the table; if  the container is not secured to the table it may be  Fenced. If a superimposed load is 
required, the loading  procedure shall comply with IS 7028 (Part 1).  
 
I.2.2.3 Operate the table between 3,4  and 6 Hz for the  predetermined period to give a peak 
acceleration in the  range of 0.5 to 1.1 g. The movement shall be such that  vertical component is 
approximately sinusoidal; a rotary movement of the table is acceptable.  
 
NOTE - If instrumentation used to determine the vibration  level, the accelerometer should be  
attached to the table near the container, but protected so that the test container shall  not come 
into contact with it. For testing at 1.1 g, in place of  instrumentation, the proper freq uency setting 
may be dete rmined by starting the vibration of the table at a frequency of about 2 Hz. and 
steadily increasing the frequency until some portion of the container repeatedly leave s the 
table, to ensure that the container receives a continuing series of repetitive shocks . 
 
I.2.2.4 At the end of the test period, the closure shall show no  indication of leakage.